A United States-led coalition strike killed at least 33 people after war planes bombed a school that was used as a center for displaced citizens, the Syrian Observatory for Human Rights reported on Wednesday. An activist working with the Britain-based monitor said 33 bodies were removed from the debris in Mansoura.

“They are still pulling bodies out of the rubble. Only two people were pulled out alive,” said the head of the observatory, Rami Abdel Rahman, according to The Guardian. Reports of the strike emerged while representatives of 68 nations are in Washington DC, USA, to discuss ways to counter the extremist Islamic State group in the region.

Local residents of the area told the organisation that the school had sheltered around 40 displaced families from Al-Raqqah, Homs and Aleppo. The monitor said Wednesday’s incident had raised the toll to 116 civilians since March 8.

The coalition has been fighting the radical group since 2014. “I recognise that there are many pressing challenges in the Middle East, but defeating the ISIS [Islamic State of Iraq and Syria] is the United States’ number one goal in the region,” US Secretary of State Rex Tillerson told the conference in Washington.

Earlier this month, the coalition had admitted to unintentionally killing at least 220 civilians in Syria and Iraq, The Guardian reported. More than 3.2 lakh people have been killed and lakhs of others have been displaced by the violence that has ravaged the nations since March 2011.